Textured composite cleaning device

ABSTRACT

A multi-material composite, the materials being positioned at raised regions ( 120/220/320/420 ) and recessed regions ( 130/230/330/430 ) on the working surface ( 110/210/310,315/410 ), provides a cleaning device ( 100/200/300/400 ) with both scouring and wiping on a single surface. By recessing certain material (s) from the working surface, the user can control, with pressure, the extent to which the recessed region makes contact with a surface to be cleaned ( 170/270 ). The composite may have at least a first substrate ( 140/240/340/440 ) that is a compressible material, and a second substrate ( 150/250/350/450 ) that is a compressible material.

BACKGROUND

The present disclosure relates to a textured composite cleaning device.In particular, the present disclosure relates to a cleaning device thatcomprises a combination of materials with the materials providing araised region and a recessed region.

When cleaning or washing surfaces such as kitchen countertop, bathroomtile, dishes, or pots and pans, it is often necessary to scour from thesurface stuck-on food, grease, dirt, or other debris. However, it isoften also necessary to wipe the surface clean of the removed food,grease, dirt, or debris following scouring. Also, it may be necessary towipe the surface clean of excess liquid. It is common to use scrubsponges, such as a Scotch-Brite® Scrub Sponge, for scouring and wiping asurface. Such scrub sponges are highly effective at scouring and wiping.However, the scouring and wiping surfaces are opposite to one anotherand require changing between the surfaces to facilitate both scouringand wiping.

SUMMARY

A multi-material composite with appropriately positioning the materialsat a raised region and a recessed region on the working surface canprovide a cleaning tool with both scouring and wiping on a singlesurface. By recessing certain materials from the working surface, theuser can control, with pressure, the extent to which the recessedsurface can make contact with the surface to be cleaned.

In general, the cleaning device comprises a composite having at leastfirst and second substrates, wherein at least one of the substrates is acompressible material, and the other substrate is a compressiblematerial or an incompressible material. In one embodiment, the cleaningdevice comprises a composite having at least a first substrate that is acompressible material and a second substrate that is a compressiblematerial. In another embodiment, the cleaning device comprises acomposite having at least a first substrate that is a compressiblematerial and a second substrate that is an incompressible material. Inyet another embodiment, the cleaning device comprises a composite havingat least a first substrate that is an incompressible material and asecond substrate that is a compressible material.

In general, the composite includes a working surface including aplurality of recessed regions and a plurality of raised regions. Atleast a portion of the first substrate is exposed at the recessed regionof the working surface. At least a portion of the second substrate isexposed at the raised region of the working surface.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side view of a first embodiment of a cleaning device;

FIG. 2 is a side view of the first embodiment in use;

FIG. 3 is a perspective view of a second embodiment of a cleaningdevice;

FIG. 4 is a perspective view of the second embodiment in use;

FIG. 5 is a side view of a third embodiment of a cleaning device;

FIG. 6 is a side view of a fourth embodiment of a cleaning device

While the above-identified drawings and figures set forth embodiments ofthe invention, other embodiments are also contemplated, as noted in thediscussion. In all cases, this disclosure presents the invention by wayof representation and not limitation. It should be understood thatnumerous other modifications and embodiments can be devised by thoseskilled in the art, which fall within the scope and spirit of thisinvention.

The figures may not be drawn to scale.

DETAILED DESCRIPTION

FIG. 1 is a side view of a first embodiment of a cleaning device 100.FIG. 2 is a side view of the cleaning device 100 shown while being usedto wipe a surface 170. The cleaning device 100 is a composite comprisingat least a first substrate 140 and a second substrate 150. The cleaningdevice 100 includes a working surface 110 that is textured having aplurality of raised regions 120 and a plurality of recessed regions 130.

The first substrate 140 and second substrate 150 are connected to oneanother in such a way to form a composite. In this embodiment, the firstsubstrate 140 forms a layer while the second substrate 150 forms anotherlayer, that is directly adjacent the layer of the first substrate. Inone embodiment, the first and second substrates are connected throughadhesive, lamination, or heat fusion. In this embodiment, the firstsubstrate 140 forms the raised regions 120, while the second substrate150 forms the recessed regions 130.

The first substrate 140 is a solid, compressible material having aworking, compressible thickness. The second substrate 150 is a solid,compressible material having a working, compressible thickness.Therefore, very thin films or thin woven, nonwoven, or knitted wipes arenot suitable for the first or second substrate. In one embodiment, thecleaning device 100 has a thickness of at least 1 cm.

Suitable materials that are solid, compressible materials useful for thefirst and second substrates include all types of foams and compressiblescouring materials, such as lofty fiber webs. The first substrate 140and second substrate 150 may both be foams, both be scouring materials,or one may be a foam and one may be a scouring material. When both arefoams or both are scouring materials, the first and second substratesmay comprise foams different from one another or scouring materialsdifferent from one another.

Examples of suitable foams include synthetic foams or cellulose sponge.Synthetic foams are particularly well suited because the foam is aflexible, compliant material that can contour over the surface beingcleaned and can absorb liquid. The synthetic foam could be an open cellfoam or a closed cell foam. Synthetic foams, particularly open cellsynthetic foams, are less hydrophilic and have a low ability to retainliquid within the structure as compared to cellulose sponge. Therefore,although fluid is easily absorbed in the material, the fluid is alsoeasily flushed from the less hydrophilic foam. It is believed that thefast flushing through the pores of the less hydrophilic foam causes soapto become very sudsy as it passes in and out of the foam. Further,because the less hydrophilic foam does not readily retain liquid withinthe structure, a synthetic foam will dry faster than a more hydrophilicmaterial such as cellulose sponge.

Synthetic sponge may be made from rubber, polyether, polyester,melamine, neoprene, SBR, butadiene, nitrile, EPDM, ECH, polystyrene,polyethylene, polypropylene, polyurethane, EVA, EMA, metallocene resin,PVC, melamine or blends of any of the above, and the like. It isunderstood that different materials for a synthetic sponge or evendifferent properties within a synthetic sponge can result in syntheticsponges having different compressibility. Therefore, for example, a PVCsponge with large pores may be used as the first substrate, while a PVCsponge with small pores may be used as the second substrate because eachof these PVC sponges has different properties such as compressibility.

Cellulose-based sponges can be used as one of the first or secondsubstrates. Cellulose-based sponges can include those which are derivedfrom plant products for example. Cellulose sponge provides aparticularly unique wiping surface because cellulose sponge is flexibleand conformable and is a hydrophilic sponge that is capable of absorbingand retaining fluids. Therefore, when a damp cellulose sponge is wipedover a surface, large amounts of liquid are not deposited onto thesurface being wiped. Further, spills of liquids can be absorbed andretained in the cellulose sponge until the cellulose sponge is squeezed.

Compressible scouring materials may be used for the substrates. Examplesof compressible scouring materials include compressible, interconnectedfibers. Fibers can be interconnected as knitted, woven, or nonwoven websof fibers. The fibers may be natural, synthetic or a combination ofnatural and synthetic fibers. Typically a compressible scouring materialis relatively rigid. To achieve the rigidity, stiff fibers may be usedand/or the fibers may be coated with a binder. It is understood thatcertain foams having sufficient rigidity may also function as acompressible scouring material. For example, foamed melamine is wellsuited for scouring.

Second substrate 150 may comprise an incompressible material incombination with first substrate 140 comprising a compressible material.In general, incompressible materials are those which, when subjected tomanual compression by a typical user, do not change significantly involume at least to the eye of the user. Exemplary incompressiblematerials include rigid foams and various types of rigid abrasive webs.

The side view in FIG. 1 shows a first row 111 of raised regions 120 andbehind the first row is a second row 112 of raised regions. This surfacetopography is commonly referred to a “convoluted.” In this embodiment,the raised regions 120 are discrete and are spaced from one another, andthe recessed regions 120 are discrete and are spaced from one another.Typically, a convoluted surface topography has a “mirror image” of theraised regions and recessed regions. The raised regions 120 are alignedgenerally linearly; however, from row to row, as can be seen in FIG. 1,the raised regions 120 are off set from one another. Macroscopically,this arrangement of raised regions 120 and recessed regions 130 providesboth the first substrate and second substrate across the entire workingsurface. Therefore, both the first substrate and second substrate arereadily accessible to the user.

In this embodiment, the uppermost portion 124 of the raised regions 120are convexly curved, while the lowermost portion 134 of the recessedregions 130 are concavely curved. Therefore, the side walls between theuppermost portion 124 and the lowermost portion 134 are sloping and havean inflection point. In this embodiment, the inflection point isapproximately midway between the uppermost portion 124 of the raisedregion 120 and the lowermost portion 134 of the recessed region 130.With the sloping side walls, the perimeter of the raised region 120 getslarger closer to the recessed region 130. Therefore, upon compression ofthe first substrate 140, the underlying second substrate 150, having alarger diameter, becomes more readily available to the working surface110. Also, when compressing the raised region, it is believed thatslightly less force is required to compress the first substrate becauseless material will stack against itself as compared to a more cubeshaped raised region with linear side walls. It is understood that theside walls may be straight lines and not curved and that the surfaces ofthe raised region and/or the recessed region may also be flat and notcurved.

In the embodiment shown in FIG. 1, the first substrate 140 forming theraised region 120 is a foam and the second substrate 150 forming therecessed region 130 is a compressible scouring material that is shown asa nonwoven web of fibers. In this embodiment, the foam is morecompressible than the nonwoven web. This combination of materials forthe raised regions and recessed regions provides a working surface thatcan wipe with the foam when light pressure is applied and can scour withthe nonwoven web when heavy pressure is applied to compress the foam.With light pressure, the side walls can provide additional surface areafor wiping or slight scouring. FIG. 2 (where the second row 112 has beenremoved for clarity in viewing) clearly shows that under heavy pressurethe foam raised regions 120 are compressed to bring the recessed regions130 into contact with the surface 170 being cleaned. Therefore, a singleworking surface 110 can provide both wiping and scouring through theselective engagement of the raised regions 120 and the recessed regions130.

FIG. 3 is a perspective view of a second embodiment of a cleaning device200. FIG. 4 is a side view of the cleaning device 200 shown in FIG. 3while being used to wipe a surface 270. The cleaning device 200 is acomposite comprising at least a first substrate 240 and a secondsubstrate 250. As in FIG. 1, the first substrate 240 is a layer and thesecond substrate 250 is an adjacent layer. The cleaning device 200includes a working surface 210 that is textured having a plurality ofraised regions 220 and a plurality of recessed regions 230. The cleaningdevice 200 is shown in FIG. 3 as a square-shaped device. It isunderstood that the other embodiments disclosed herein could have asimilar to that shown in FIG. 3. It is also understood that any othershapes could be used.

The first substrate 240 forms the raised regions 220, while the secondsubstrate 250 forms the recessed regions 230. In this embodiment, theraised regions 220 are discrete and are spaced from one another byrecessed regions 230. The raised regions 220 extend from one end of thecleaning device 200 to another end. In this embodiment, the raisedregions 220 are linear and are parallel to one another. Therefore, therecessed regions 230 are linear and are parallel to one another butseparated from one another by the raised regions 220.

The uppermost portion 224 of the raised regions 220 are convexly curved,while the lowermost portion 232 of the recessed regions 230 areconcavely curved. Therefore, the side walls are sloping and have aninflection point. In this embodiment, the inflection point isapproximately midway between the uppermost portion 224 of the raisedregion 220 and the lowermost portion 232 of the recessed region 230.With the sloping side walls, the perimeter of the raised region 220 getslarger closer to the recessed region 230. Therefore, upon compression ofthe first substrate 240, it is believed that slightly less force isrequired to compress the first substrate because less material willstack against itself as compared to a more cube shaped raised regionwith linear side walls. Also, the side walls are more accessible forwiping or scouring to provide cleaning surface area for materialprojecting upward from the surface 270 being cleaned.

In the embodiment shown in FIG. 3, the first substrate 240 forming theraised region 220 is a compressible scouring material that is shown as anonwoven web, and the second substrate 250 forming the recessed region230 is a foam. In this embodiment, the foam is more compressible thanthe nonwoven web. This combination of materials for the raised regions220 and recessed regions 230 provides a working surface that is highlyeffective for scouring. With light pressure applied, the uppermostportion 224 of the raised region 220 can scour. With heavy pressure, theraised regions 220 will slightly compress providing an even stiffer,more rigid material for scouring. Also, the side walls are useful toscouring away material projecting upward from the surface being cleaned.The recessed region 230 being a compressible foam provides for overallflexibility of the cleaning device 200. With the more rigid secondsubstrate 250 disconnected in areas, the cleaning device can easilyflex, bend, and contour over a surface 270 to be cleaned. Also, therecessed region 230 being a compressible foam provides a conformable andcomfortable surface for holding. In addition, with heavy pressureapplied, the foam can make contact or near contact with the surface 270being cleaned to wipe or absorb liquid on the surface. Therefore, asingle working surface 210 can provide both wiping and scouring throughthe selective engagement of the raised regions 220 and recessed regions230. It is also contemplated that first substrate 240 may comprise anincompressible material in combination with second substrate 250comprising a compressible material.

FIG. 5 is a side view of a third embodiment of a cleaning device 300.The cleaning device 300 is a composite comprising at least a firstsubstrate 340 and a second substrate 350. In this embodiment, the secondsubstrate 350 is embedded with and distributed throughout the firstsubstrate 340.

The cleaning device 300 includes a first working surface 310 that istextured having a plurality of raised regions 320 and a plurality ofrecessed regions 330 and a second working surface 315 that is texturedhaving a plurality of raised regions 320 and a plurality of recessedregions 330. Therefore, it is understood that a single cleaning device300 can have a single textured working surface (FIGS. 1-4) or more thanone textured working surface (FIG. 5).

Also, although the second working surface 315 is shown to have similarraised regions 320 and recessed regions 330. However, in thisembodiment, the raised regions 320 of the second working surface 315 areoffset from the raised regions 320 of the first working surface 310. Inthis embodiment, a third substrate 360 in included at the raised region320 on the second working surface 315. It is understood that thesubstrates used for the different working surface may be the same ordifferent from one another and the arrangement and configuration of thedifferent working surface may be the same or different from one another.For example, a cleaning device may have a first working surface as shownby working surface 310 in FIG. 5 and a second working surface as shownby working surface 210 in FIG. 3.

In the embodiment shown in FIG. 5, the second substrate 350 is embeddedand distributed throughout the first substrate 340. Therefore, at thefirst working surface 310 a portion of the first substrate 340 forms theraised regions 320 and the recessed region 330, and a portion of thesecond substrate 350 forms the raised regions 320 and the recessedregions 330. At the second working surface 315 the third substrate 360forms the raised regions 320 and a portion of the first substrate 340and a portion of the second substrate 350 forms the recessed region 330.In this embodiment, the raised regions 320 are discrete and are spacedfrom one another by recessed regions 330 and the recessed regions 330are discrete and are spaced from one another by raised regions 320. Theshape and configuration of the raised regions 320 and recessed regions330 at both the first working surface 310 and second working surface 315is “convoluted” as shown and described for FIGS. 1 and 2. Raised regions320 in this embodiment include side walls that are generally sloping.The uppermost portion 324 of the raised region 320 is a convex curvedsurface. The lowermost portion 332 of the recessed region 330 isconcavely curved.

In the embodiment shown in FIG. 5, the first substrate 340 is a foam andthe second substrate 350 is a fiber cluster embedded within the foam.The fiber cluster is less compressible than the foam. Such a material isshown and described in U.S. patent application Ser. No. 12/421,753titled “Cleaning Sponge” filed on Apr. 10, 2009. Therefore, overall thecleaning device 300 is compressible wherein when force is applied thefoam is compressed and the fiber clusters provide scouring over asurface being cleaned. The third substrate 360 is a compressiblescouring material shown as a nonwoven web of fibers. This combination ofmaterials, wherein the first substrate 340 and second substrate 350comprise both the raised regions 320 and recessed regions 330 provides aworking surface that is highly effective for wiping because the foam isthroughout the entire working surface. In addition, with application oflight and firm pressure the working surface is effective for scouring.By controlling the pressure applied to the cleaning device 300, the usercan control the extent to which the fiber clusters of the secondsubstrate 350 are pressed against the surface being cleaned. As with theother embodiments, the side walls of the raised region, which includesthe first substrate 340 and second substrate 350, can be effective forscouring material raised from a surface to be cleaned and also provideadditional surface area to absorb liquid extending from a surface to becleaned. As with the other embodiments, a single working surface 310 or315 can provide both wiping and scouring through the selectiveengagement of the raised regions 320 and recessed regions 330.

The third substrate 360, forming the raised region 320 at the secondworking surface 315 that is aligned with the recessed region 330 of thefirst working surface 310, aids in pressing the recessed region 330 atthe first working surface into contact with a surface to be cleanedbecause more material is forced under pressure into the backside of therecessed region 330 at the first working surface 310. This is true forthe opposite: the second working surface 315.

Additional embodiments of the cleaning device shown in FIG. 5 arecontemplated in which the first and third substrates, 340 and 360,respectively, are either compressible or incompressible, as long as oneof the two substrates is compressible. For example, first substrate 340may be a compressible material, and third substrate 360 anincompressible material. For another example, first substrate 340 may bean incompressible material, and third substrate 360 a compressiblematerial.

FIG. 6 is a side view of a fourth embodiment of a cleaning device 400.The cleaning device 400 is a composite comprising a first substrate 440,a second substrate 450, and a third substrate 460. The cleaning device400 includes a working surface 410 that is textured having a pluralityof raised regions 420 and a plurality of recessed regions 430.

The first substrate 440, second substrate 450, and third substrate 460are connected to one another in such a way to form a composite. In thisembodiment, each of the substrates forms a layer. In this embodiment,the first substrate 440 forms the uppermost portion 424 of the raisedregions 420, the second substrate 450 forms the recessed regions 430,and the third substrate 460 is positioned between the first substrate440 and the second substrate 450 and is in a midportion of the raisedregion 420. Adjacent materials are different from one another; howeverseparated materials, such as first substrate 440 and second substrate450 can be the same as one another or can be different from one another.

In the embodiment shown in FIG. 6, the raised regions 420 are discreteand are spaced from one another by the recessed regions 430. Therecessed regions 430 are discrete and are spaced from one another by theraised regions 420. Generally, the arrangement of the “convoluted”raised regions and recessed regions is similar to that shown in FIGS.1-2. Raised regions 420 in this embodiment include side walls that aregenerally sloping. The uppermost portion 424 of the raised region 420 isa convex curved surface. The lowermost portion 432 of the recessedregion 430 is concavely curved. The curvature is nearly continuous suchand the side walls generally do not form a straight line. It is believedthat this sloping of the side walls provides more surface area availablefor contact with a surface being cleaned when the cleaning device 400 ispassed over the surface and pressure is applied. With very slightpressure applied to the cleaning device 400, the underlying thirdsubstrate 460, being larger in diameter than the upper most firstsubstrate 440 can come into contact with a surface being cleaned.

In the embodiment shown in FIG. 6, the first substrate 440 forming theraised region 420 is a foam, the second substrate 450 forming therecessed region 430 is a foam, and the third substrate 460 forming atthe midportion of the raised region 420 is a compressible scouringmaterial shown as a nonwoven web of fibers. In this embodiment, the foamis more compressible than the nonwoven web. This combination ofmaterials for the raised regions and recessed regions provides a workingsurface that can wipe with the foam at the uppermost portion 424 of theraised region and when pressure is applied, the first substrate 440compresses to provide the larger diameter third substrate 460 availablefor scouring. Therefore, a single working surface 410 can provide bothwiping and scouring through the selective engagement of the raisedregions 420 and recessed regions 430.

Additional embodiments of the cleaning device shown in FIG. 6 arecontemplated in which the first, second and third substrates are somecombination of compressible and incompressible materials, as long as oneof the three substrates is compressible. For example, first and thirdsubstrates, 440 and 450 respectively, may be compressible materials, andthird substrate 460 an incompressible material. For another example,first and third substrates, 440 and 450 respectively, may beincompressible materials, and third substrate 460 a compressiblematerial.

Another embodiment of the cleaning device is similar to the devicedescribed for FIG. 5, except that the first substrate forming the raisedregion is a compressible scouring material shown such as a nonwoven webof fibers, the second substrate forming the recessed region is acompressible scouring material such as a nonwoven web of fibers, and thethird substrate forming at the midportion of the raised region is afoam. Adjacent materials are different from one another; howeverseparated materials, such as first substrate and second substrate can bethe same as one another or can be different from one another.

A variety of embodiment has been disclosed. It is understood any manydifferent combinations of materials may be used for the differentsubstrates so long as one material is more compressible than the secondmaterial. Also, it is understood that many different substrates may beincluded to form the composite of the cleaning device. As was shown withFIGS. 1, 3, and 6, multilayer arrangement of the substrates may be usedto provide the composite and resulting arrangement of the substrates atspecified locations on the raised region and recessed region. It isunderstood that the entire raised portion may include the firstsubstrate while only the lowermost portion of the recessed region mayinclude the second substrate. It is understood that the uppermostportion may include the first substrate, while the lowermost portion andnearly the entire remaining raised region may include the secondsubstrate. One or more working surfaces may be included having a varietyof shapes, configurations, and arrangements of the raised region andrecessed region.

As was already discussed, the working surface is used over a surface tobe cleaned to wipe or scour the surface. Various amounts of pressure areapplied to the cleaning device to selectively engage portions of theraised region or the recessed region.

To make the cleaning device, first the composite is formed. This may bea layered structure with the layers secured together or may be astructure with embedded material (FIG. 5). Once the composite is formed,the material is then “convoluted.” By convoluting, the composite ispassed through a nip between a pair of rollers having interdigitatedprojections to compress different portions of the layer of compositetoward its opposite side surfaces and then slitting the compressed layerof composite with a blade to produce two halves of the layer ofcomposite each with raised regions and recessed regions. Other types ofcutting devices can be used to cut the substrates.

Although specific embodiments of this invention have been shown anddescribed herein, it is understood that these embodiments are merelyillustrative of the many possible specific arrangements that can bedevised in application of the principles of the invention. Numerous andvaried other arrangements can be devised in accordance with theseprinciples by those of ordinary skill in the art without departing fromthe spirit and scope of the invention. Thus, the scope of the presentinvention should not be limited to the structures described in thisapplication, but only by the structures described by the language of theclaims and the equivalents of those structures.

1-20. (canceled)
 21. A cleaning device comprising: a composite having atleast a first substrate that is a compressible material and a secondsubstrate that is a compressible material; wherein the compositeincludes a working surface including a plurality of recessed regions anda plurality of raised regions; wherein at least a portion of the firstsubstrate is exposed at the recessed regions of the working surface;wherein at least a portion of the second substrate is exposed at theraised regions of the working surface.
 22. The cleaning device of claim21, wherein the first substrate requires a higher force to compress thanthe second substrate.
 23. The cleaning device of claim 21, wherein thefirst substrate is a nonwoven scouring web and the second substrate is afoam.
 24. The cleaning device of claim 21, wherein the second substraterequires a higher force to compress than the first substrate.
 25. Thecleaning device of claim 21, wherein the first substrate is a foam andthe second substrate is a nonwoven scouring web.
 26. The cleaning deviceof claim 21, wherein the second substrate comprises a plurality ofdiscrete fiber clusters embedded throughout the first substrate, whereineach fiber cluster comprises a matrix of interconnected fibers.
 27. Thecleaning device of claim 21, wherein an uppermost portion of the raisedregion is entirely the second substrate and the lowermost portion of therecessed region is entirely the first substrate.
 28. The cleaning deviceof claim 21, wherein the second substrate is exposed in a middle portionof the raised region.
 29. The cleaning device of claim 21, wherein theentire raised region comprises the second substrate.
 30. The cleaningdevice of claim 21, wherein the raised regions have a concavely curvedsurface and the recessed regions having a convexly curved surface. 31.The cleaning device of claim 21, wherein the raised regions are discreteand separated from one another by recessed regions.
 32. The cleaningdevice of claim 21, wherein the recessed regions are discrete andseparated from one another by raised regions.
 33. The cleaning device ofclaim 21, wherein the working surface comprises a plurality of discreteraised regions each extending from one edge of the cleaning device toanother edge of the cleaning device and separated from one another by arecessed region extending from one edge of the cleaning device toanother edge of the cleaning device.
 34. The cleaning device of claim21, wherein a first row of raised regions and recessed regions is offsetfrom an adjacent second row of raised regions and recessed regions. 35.A cleaning device comprising: a working surface having a plurality ofraised regions each having a convexly curved surface and a plurality ofrecessed regions each having a concavely curved surface; wherein a baselayer forms the recessed regions; wherein a top layer forms an upperportion of the raised regions; wherein a third layer, between the baselayer and top layer, forms a middle portion of the raised regions. 36.The cleaning device of claim 35, wherein the base layer and the toplayer are foams, and the third layer is a nonwoven scouring web.
 37. Thecleaning device of claim 35, wherein the base layer and the top layerare nonwoven scouring webs, and the third layer is a foam.
 38. Acleaning device comprising: a sponge body with a plurality of discretefiber clusters embedded within the sponge body, wherein each fibercluster comprises a matrix of interconnected fibers, and wherein aworking surface of the sponge body has a plurality of raised regionseach having a convexly curved surface and a plurality of recessedregions each having a concavely curved surface.